1. Field of the Invention
The present invention relates to multi-screen display technology, and in particular relates to a graphics card, a multi-screen display system and a synchronous display method.
2. Description of the Related Art
Because it is difficult to manufacture a large-sized panel, a video wall consisting of a plurality of screens is generally used to display a large picture. FIG. 1A depicts an exemplary embodiment of a video wall. As shown, a video wall 100 consists of multiple screens. The multiple screens may be controlled by a single or multiple graphics cards attached to a computer. In conventional multi-screen display systems, the multiple screens are typically controlled by more than one graphics cards. The graphics cards are connected by cables, as shown in FIG. 1B. When a clock signal Gen_CLK is generated by one of the graphics cards, the cables transfer the generated clock signal Gen_CLK to the remaining graphics cards to synchronously display images on the multiple screens.
The cables, however, occupy considerable space and complicate the overall design of the system. In a case wherein a large number of graphics cards are connected by cables, the clock signal Gen_CLK conveyed on the cables may be degraded, and may be interfered with by noise, and the synchronous display of the multiple screens may be badly affected. When the multiple graphics cards are driven by asynchronous clock signals, unsightly fissure may occur on the displayed image. Therefore, it is important to synchronize the multiple screens of the video wall 100.